1. Field of the Invention
The present invention relates to snap ring pliers, and more particularly to snap ring pliers provided with a lock member which is operated in a labor-saving flexible way.
2. Description of the Prior Art
A snap ring is shaped as C and used to retain elements (e.g., bearings or shafts) within a bore. The snap ring has certain elasticity itself to be expanded or contracted. In order to install the snap ring on a desired article, special pliers are required to contract or expand the snap ring so as to position the span ring on a workpiece. For conventional snap ring pliers, the user grips two handles of the pliers to operate the snap ring. The gripping members of the jaws of the pliers are opened or closed to expand or contract the snap ring. The operation is controlled by the user's feeling. That is to say, when the snap ring is contracted or expanded to a predetermined deformation, the user has to control the exerting force exactly. When the operation is inappropriate, the snap ring may fall before positioned. The stored elastic energy of the deformed snap ring may cause the snap ring to fly, hit and hurt the individual who holds the snap ring pliers.
The applicant invented snap ring pliers, disclosed in Taiwan Utility Model Reg. No. M409924 (U.S. Pat. No. 8,347,471), overcome the shortcomings of the conventional snap ring appliers. The snap ring pliers are operated conveniently and save for use. For the hook portion of the elastic plate to engage with the teeth stably and firm, a thick elastic plate is required.
However, the operation for the lock member to hold the elastic plate upward is laborious. If a thin elastic plate is used, the hook portion cannot be compressed or limited to cause the hook portion to bounce unexpectedly or disengagement. Thus, the need for improvement still exists.